Freshwater ecosystem vulnerability: Is native climatic niche good enough to predict invasion events?

Abstract

Abstract The introduction of invasive species is a significant threat to freshwater ecosystems and is changing the biogeographic patterns of fish species, leading to homogenization of fish fauna. The ability to predict potential invasions is critical in conservation biology to avoid further biodiversity loss. Ecological niche modelling has become an important tool in biological invasion studies. However, some introduced species can spread to habitats that are different from those in their native range. A framework based on niche shifts and ecological niche models was used to show that Pterygoplichthys ambrosettii, an armoured catfish, commonly known as ‘pleco', and native to the middle‐lower Paraná river, has expanded its niche by 27% and is now occupying a new range of environmental conditions. This species has experienced a niche shift from its original habitat and has started to occupy new areas of the Upper Paraná river basin and the São Francisco basin in Brazil. Models built using both native and non‐native areas were not able to predict the invaded habitats, and in either the native or non‐native areas the cross‐validation procedures corroborate the niche expansion hypothesis.